Fountain pen



FIG. 1 is a front elevational view of a fountain pen showing my new design;

FIG. 2 is a rear perspective view thereof;

FIG. 3 is a right side perspective view;

FIG. 4 is a right side perspective view with the cap deposed on the end remote from the writing point;

FIG. 5 is a perspective view of the fountain pen with a cap separated from the barrel; and

FIG. 6 is a left side perspective view with a cap deposed on the end remote from the writing point. 

The ornamental design for a fountain pen, as shown and described. 